The present invention relates to over-the-air programming of telecommunication services. More particularly, the present invention provides dynamic updating of mobile station databases to provide flexible telecommunication services.
An industry standard referred to as IS-136 defines a standard for mobile stations which communicate in the cellular and PCS bands. The standard defines the basic functionality of the mobile station as well as the communication protocols between the mobile station and a mobile station switching center. One of the important aspects of a mobile station designed in accordance with this standard is the programmability of the station to be flexible in its operation.
The mobile stations employing this particular standard have been recognized as being useful for implementing a feature known as Intelligent Roaming (IR). This is a process that a mobile station or phone goes through to assure that it is receiving the best service possible regardless of the location that the phone is in.
The following description provides the background for understanding the significance of intelligent roaming in the mobile environment. This should be understood as providing merely an example of one particular telecommunication service which is available using an IS-136 mobile station.
FIG. 1 illustrates a portion of the radio frequency spectrum. Frequency range 10 centered around 800 MHz has historically been known as the cellular frequency range and frequency range 12 centered about 1900 MHz is a newer defined frequency range associated with Personal Communication Services (PCS). Each range of frequencies, i.e., the cellular and PCS are broken into two portions. In cellular frequency range 10, there is up-link portion 14 which is used for communications from a mobile communication device to a base station such as a cellular base station. Portion 16 of cellular frequency range 10 is used for down-link communications, that is, communications from a cellular base station to a mobile communication device. In a similar fashion, portion 18 of PCS frequency range 12 is used for up-link communications, that is, communications from a mobile communication device to a base station. Portion 20 of PCS frequency range 12 is used for down-link communications, i.e., communications from a base station to a mobile communication device.
Each of the frequency ranges is broken into bands which are typically associated with different service providers. In the case of cellular frequency range 10, frequency bands 30 and 32 are designated band "a" for up-link and down-link communications respectively. In a particular geographic area, a cellular service provider is assigned frequency band "a" to carry out mobile communications. Likewise, in the same geographic area another cellular service provider is assigned frequency bands 34 (up-link) and 36 (down-link) which are designated "b". The frequency spectra assigned to the service providers are separated so as to not interfere with each other's communications. This enables two separate service providers to provide cellular service in the same geographic area.
The U.S. government has auctioned the PCS frequency spectra to service providers. As with the cellular frequency range, the PCS frequency range is broken into several bands where a different service provider may use a particular frequency band for which it is licensed within a particular geographic area. The PCS bands are referred to as A, B, C, D, E, and F. The A band includes up-link band 50 and down-link band 52. The B band includes up-link band 54 and down-link band 56. Band C includes up-link band 58 and down-link band 60. Each up-link and down-link band of the A, B, and C bands are approximately 30 MHz wide. The D band includes up-link band 62 and down-link 64. The E band includes up-link band 66 and down-link band 68. Likewise, band F includes up-link band 70 and down-link band 72. The up-link and down-link bands of bands D, E and F are approximately 10 MHz wide each. It should be noted that with these cellular and PCS frequency bands it is possible to have as many as eight different wireless communication service providers in a particular area.
Each of the different cellular and PCS bands consist of control channels and communication channels in both the up-link and down-link direction. In the case of analog cellular bands there are twenty-one control channels for the "a" and "b" bands. Each of the control channels include an up-link and down-link portion. The control channels transmit information such as a System Operator Code (SOC), a System Identifier Code (SID), paging information, call set-up information and other overhead information, such as information relating to registering with the mobile communication system.
A portion of the cellular band's spectrum not occupied by the control channels is used for communication channels. Communication channels carry voice or data communications, where each channel consists of an up-link or down-link communications link. Presently, there are several cellular communication standards. An analog standard known as EIA/TIA553 was built upon the AMPS (Advanced Mobile Phone Service) standard. This standard supports twenty-one Analog Control Channels, (ACC) and several hundred Analog Voice or Traffic Channels (AVC). A newer standard is the EIA/TIA IS54B standard which supports dual mode operation. Dual mode operation refers to having an analog control channel, and either an analog/traffic channel or a Digital Traffic Channel (DTC). The AVC or DTC are used for actual communications, and the ACC is used to transfer information relating to, for example, call set-ups, service provider identification and the other overhead or system information. The EIA/TIA IS136 standard supports communications covered by both analog and dual mode cellular, and also includes a totally digital communication scheme which was designed for the PCS frequency bands A to F and cellular frequency bands "a" and "b". This standard allows for a digital traffic channel and a digital control channel (DCCH). In the case of the DTC, not only is the voice or data communicated, but in addition, a digital channel locator (DL) is transmitted to the DTC. The DL enables a mobile communication device that locks onto the DTC to use the information in the DL to locate a DCCH for purposes of obtaining information such as the SOC, SID, paging information and other system overhead information carried on the digital control channel.
When a mobile communication device such as a mobile telephone, attempts to register with the service provider, it locks onto a control channel and reads information such as the SOC and SID. If the SOC and/or SID correspond to a service provider with which the user has a communication services agreement, the telephone may register with the service provider's mobile communication system via the up-link control channel.
FIG. 2 illustrates a map of the United States illustrating cities such as Seattle, Chicago and Washington, D.C. For example, in Seattle frequency band A has been licensed to SOC 001 with a SID of 43 and band C has been licensed to SOC 003 with a SID of 37. In Chicago, suppose that frequency band C has been licensed to SOC 001 with a SID equal to 57, and that band B has been licensed to SOC 003 with a SID of 51. In Washington, D.C. suppose that frequency band "a" has been licensed to SOC 001 with a SID of 21, and that band A has been licensed to SOC 003 with a SID of 17. It should be noted that the same SOC may be found in several different locations although on different frequency bands. It should also be noted that the same SOC will be associated with different SIDs in each geographical area and that in the same geographic area different service providers have different SIDs. If a particular subscriber to a wireless communication service has an agreement with a service provider having a SOC of 001, that subscriber would prefer to use systems with a SOC of 001 because the subscriber is likely to receive a less expensive rate. When the subscriber is in Seattle, he or she would prefer to be on band A, and if in Chicago, on band C, and if in Washington, D.C., on band "a". The above described situation presents a problem for a wireless communication subscriber. As the subscriber moves from one area of the country to another, the telephone when turned on, searches for the "home" service provider or the service provider with which the subscriber has a prearranged agreement. If, for example, the subscriber travels from Seattle to Chicago, when turning the phone on in Chicago, the phone will search through the different bands of the spectrum to identify the service operator with the code 001 in order to find the desired service provider.
In a co-pending application assigned to the same assignee as the present invention, the inventors recognized that it was beneficial to take advantage of the database capabilities within the IS-136 mobile stations and store information to control the process by which a mobile station searches for a service channel when it is out of the its home region. This concept is referred to as Intelligent Roaming (IR). This concept is described in U.S. Ser. No. 08/570,905 entitled "A Method for Selecting a Wireless Communications Service Provider in a Multi-Service Provider Environment", now U.S. Pat. No. 5,832,367. Other applications directed to Intelligent Roaming include: U.S. Ser. Nos. 08/570,904; 08/570,903; and 08/570,902, all are still pending before the Office.
While the IR functionality provides improved teleservice for subscribers, it nonetheless does not take full advantage of the programmability of the mobile station and fails to address a problem that arises specifically with respect to intelligent roaming, namely the changes in agreements between service providers. In particular, it is common in the wireless communication area that relationships between service providers will change over time. These are contractual arrangements which determine how subscribers of related services will be treated as they roam from one region to the next. It may so happen that over time two service providers can have a favorable relationship that subsequently changes to an unfavorable relationship. Under those circumstances, if the mobile station has been pre-programmed with information for intelligent roaming then it may wrongly identify a favored partner/associate service provider as the customer roams through various geographic areas. It is therefore desirable to provide a method to make the intelligence of the mobile stations available to adapt the station to such changes in provider capabilities and relationships.